Method of treating plants



United States PateritCfiice 2,723,909 Patented Nov. 15, 1955 METHOD OF TREATING PLANTS Frank Earl Denny, Yonkers, N. Y., assignor to Boyce Thompson Institute for Plant Research, Inc., a corporation of New York No Drawing. Application August 21, 1952, Serial No. 305,693

4 Claims. (Cl. 712.6)

have the specific property of delaying or inhibiting the growth of new plant tissue, and my invention provides an improved method for delaying the growth of such new tissue by contacting the plants with one of the compounds. The compounds which I use in carrying out the method of my invention are benzyl compounds of the group consisting of benzyl thiocyanate, o-chloro benzyl thiocyanate, benzyl salicylate, benzyl benzoate, benzyl acetate, and benzyl chloracetate.

The compounds may be applied to the plants in dispersed or diluted forms such as vapors, sprays, or dusts and the like.

In carrying out a method of the invention in the treatment of tubers, such as potatoes for example, one or more of the compounds may be applied to the potatoes during dormancy in such a manner that the potatoes may be stored for relatively long periods without sprouting, or they may be applied in such manner as to retard sprouting only until the end of a desired dormant period, leaving the tubers at the end of the period in condition for sprouting as would be desirable in the case of tubers intended for planting stock.

the air laden vapors circulated with fans. to effect a-suitablecontact with the storage organs. Mists of the compounds'may alsobe used. The storage organs may be coated with solutions, emulsions, or powdered carriers of the compounds. It is usually advisable to permit a sufficient entrance of oxygen, preferably in the form of air, to the container to supply the oxygen needed for respira tion.

In the treatment of potatoes, the maximum amount of compound needed to retard sprouting is about 1 gram for each kilogram of potatoes. Good results have been obtained, however, with from to /2 of that amount.

In the application of the invention to woody plants, I may, for example, apply certain of the compounds to the twigs early in the spring, more especially during dormancy, and bring about a retardation of the opening of the buds for a short period, say, from 3 to 20 days. At the end of that period the buds open and continue development in a normal or near normal rate. In other words, in accordance with the method of my invention, 1 may delay the budding without serious injury, if any, to the buds and then permit normal development to occur.

The compounds may be applied to the woody plants as vapors, sprays, or dusts. Solutions of the compounds in water or organic solvents such as acetone may be applied to the plants or sprays, or the plants may be dipped in such solutions.

In the application of the invention to dafiodils or hyacinths for example, one or more of the compounds may be applied to the young plants just as they appear above the soil following a very mild Winter, to hold back leaf development and thus allow flower stalk development to proceed at a relatively greater rate.

Various other plants, notably the grasses used in lawns, may be treated to retard the growth, advantageously in the manner described for woody plants. The compounds may be applied to the old tissue or to the new tissue to control the growth of the new tissue.

The following are examples illustrating methods carried out in accordance with the invention in which potatoes were immersed in solutions of the compounds during October and the sprouting in soil was determined during the following January.

In applying the growth regulants to storage organs, a very efiective and presently preferred method is to place the storage organs in a confined space such as a bag, box, barrel, or room, and place therein a growth regulant compound of the aforementioned group in such manner and under such conditions that the vapors contact the storage organs. The compound may be incorporated in pieces of paper or other fibrous carrier material, or mixed with inert powder such as talc or other carrier media, and the same placed in the container whereby the resulting vapors permeate the container and contact the storage organs. In the case of large containers, such as warehouses, the compounds may be vaporized by heating and 4 of the plant is effectively retarded for at least several 3. In the method of claim 1, applying the compound days and thereafter the plant will undergo at least near while in a dispersed form. normal growth and development. 4. In a method of claim 2, applying the compound 2. The method of retarding the sprouting of tubers and while in a dispersed form. bulbs which comprises contacting the tubers and bulbs 5 while in a dormant state with from 0.1 to 1.0 g. per kg. References Cited in the file of this Pawnt of a compound of the group consisting of benzyl thio- UNITED STATES PATENTS cyanate, o-chloro benzyl thiocyanate, benzyl salicylate, 2,394,916 Jones Feb 12, 1946 benzyl benzoate, benzyl acetate, benzyl chloracetate. 

1. THE METHOD OF RETARDING THE GROWTH OF PLANTS WHICH COMPRISES CONTACTING THE PLANT WHILE IN AT LEAST A PARTIAL DORMANT STATE WITH A COMPOUND OF THE GROUP CONSISTING OF BENZYL THIOCYANATE, O-CHLORO BENZYL THIOCYANATE, BENZYL SALICYLATE, BENZYL BENZOATE, BENZYL ACETATE, AND BENZYL CHLORACETATE IN SUCH CONCENTRATIONS THAT THE GROWTH OF THE PLANT IS EFFECTIVELY RETARDED FOR AT LEAST SEVERAL DAYS AND THEREAFTER THE PLANT WILL UNDERGO AT LEAST NEAR NORMAL GROWTH AND DEVELOPMENT. 